treadmill walking is at a steady incline, while nature-walking (or hiking) is at varying inclinations and terrain.
keeps you healthy and is ood for the environment
You move forward when walking on a surface, and on a treadmill you stand still.
A treadmill is a big wheel (like a hamster wheel) that prisoners turned by walking inside it. The power from the wheel was used to drive machinery in a factory (a mill).
It depends; Walking is best for weight loss where as running is better for muscle build-up.